CATALYSIS TODAY
·
2018
·
IF 4.667
Hongge Cui,Xinli Tong,Linhao Yu,Ming Zhang,Yongtao Yan,Xuli Zhuang
An efficient tandem process for the oxidative condensation of furfural (FUR) with ethanol catalyzed by the copper/azodicarboxylate system has been developed. Firstly, the hydrogen transferring between FUR and ethanol is investigated under the nitrogen atmosphere by combining the azodicarboxylate and alkali carbonates, in which the main products are furfuryl alcohol and furan-2-acrolein. In the following, the cuprous halides and molecular oxygen are supplemented into the reaction system in order to improve the yield of furan-2-acrolein; therein, it is found that furfuryl alcohol is further oxidized and the selectivity of furan-2-acrolein is obviously elevated when CuI and o-phenanthroline (Phen) are used as the co-catalysts. Under optimal reaction conditions, 82.5% conversion of FUR with 87.7% selectivity of furan-2-acrolein is obtained with the assistance of diethyl azodicarboxylate (DEAD) and potassium carbonate. At last, a possible catalytic mechanism is proposed for the oxidative condensation reaction between FUR and ethanol in the presence of O 2 .
研究领域:
化学
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生物质转化
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DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Guo-Cheng Han,Jiating Hou,Zong-Li Huang,Xiao-Zhen Feng,Zhencheng Chen,Wenxiang Xiao,Shuang Li
Heme is an active center of hemoglobin which is a porphyrin compound containing two free carboxyl groups that may exert intermolecular interaction with ferrocene dicarboxylate which can be studied by electrochemical methods. The CV experimental results from this current study showed that ferrocene dicarboxylate had a good pair of redox peaks in NaOH aqueous solution and organic solvents in a quasi-reversible electrode process. There was linear relationship between current and square root of the scan rate, belonging to diffusion-controlled redox processes. The signals from the potential and current had obvious shift after the reaction with heme, especially when the redox peaks disappeared from the organic solvents. Fc(COOH) 2 was activated to give compound Fc(OBt) 2 with saturated structure that did not show better redox peaks due to its worse solubility, hence it didn’t form hydrogen bonds with heme. DPV was used for heme assay, where the current was proportional to heme concentration in the range of 1.0-5.0 μM, with 0.7 nM detection limits.
研究领域:
生物化学
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分析化学
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DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2018
·
IF 4.521
Junmou Du,Huihuang Fang,Hongyan Qu,Jinping Zhang,Xinping Duan,Youzhu Yuan
5-Hydroxymethyl-2-furfural (HMF) is a key platform molecule for biomass utilization. The HMF derivative 2,5-furandicarboxylic acid (FDCA) by oxidation of HMF is a promising alternative for terephthalic acid as a monomer in polyethylene terephthalate. However, due to the facile purification of dimethyl furan-2,5-dicarboxylate (DMFD), an oxidative esterification derivative of HMF, is more desirable. In this work, supported Au–Cu bimetallic catalysts with Au–CuO x ( x = 0–1) nanohybrids were prepared by a reduction–oxidation pretreatment strategy. The as-prepared catalysts were used for the oxidative esterification of HMF into DMFD under base-free conditions using oxygen as sole oxidant. Activity tests showed that the optimized Au–Cu/γ-Al 2 O 3 catalyst displayed a remarkably high DMFD yield of up to 98% and a turnover frequency (TOF) value of 243 h –1 , whereas the monometallic Au and Cu catalysts exhibited poor performance. Various characterizations confirmed the strong interaction between Au nanoparticles and CuO x species, and their synergistic effect on the enhanced performance of HMF oxidative esterification. The reduction–oxidation pretreatment promoted the dispersion of CuO x and intensified the interaction of Au nanoparticles with CuO x . A plausible reaction mechanism for the oxidative esterification of HMF over Au–Cu/γ-Al 2 O 3 was proposed. This work provided new insights into the effect of reduction–oxidation pretreatment on the fabrication of supported Au–CuO x nanohybrids for the production of DMFD by HMF oxidative esterification.
研究领域:
化学工程
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催化科学
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生物质转化
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DOI
高影响因子
ChemCatChem
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2025
·
IF 3.9
Yannan Han,Jilei Xu,Beizhan Li,Qingda An,Zuoyi Xiao,Jiahui Huang
Graphical In this study, we developed a new strategy for the synthesis of long-chain dicarboxylic acid ester precursors via the aldol condensation of 2,5-diformylfuran (DFF) and methyl levulinate (MLA) in the presence of protic ionic liquids. The reaction mechanism was further investigated using nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FTIR). In this study, a series of long-chain dicarboxylic acid ester precursors were synthesized via aldol condensation reactions catalyzed by protic ionic liquids (PILs). When 2,5-diformylfuran (DFF) and methyl levulinate (MLA) were employed as substrates, the yield of long-chain dicarboxylic acid ester precursors reached 91.0% in the presence of pyrrolidine lactate. This preparation process eliminated the need for additional acids and bases, thereby minimizing the generation of waste salts, which was a common issue in base-catalyzed systems and biosynthesis methods. Nuclear magnetic resonance (NMR) characterization revealed that a strong interaction between the hydroxyl group of the catalyst and the carbonyl group of MLA facilitated the activation of the substrate for the aldol condensation reaction. Notably, the yield of dicarboxylic acid ester precursors remained stable even after five catalytic cycles, demonstrating the excellent reusability of the catalyst. Furthermore, pyrrolidine lactate exhibited broad applicability in both aldol condensation and Knoevenagel condensation reactions. This work presented a novel and sustainable strategy for the synthesis of long-chain dicarboxylic acid ester precursors.
研究领域:
化学工程
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生物基材料合成
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2025
·
IF 2.8
Yong Yang,Qingliang Meng,Zhenghong Guo,Juan Li,Zhengping Fang
A series of bio-based 2,5-thiophenedicarboxylates were successfully synthesized, and their chemical structures were characterized using Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). The influence of alkyl chain length and branching on the plasticizing properties of 2,5-thiophenedicarboxylates in poly(vinyl chloride) (PVC) was evaluated through dynamic mechanical analysis (DMA), hardness measurements, and tensile testing. It was found that the plasticizing efficiency of 2,5-thiophenedicarboxylates decreased as the alkyl chain length increased, as reflected by the gradual increase in glass transition temperature ( T g ), hardness, and elastic modulus. Additionally, among 2,5-thiophenedicarboxylate isomers with the same molecular weight, those with branched alkyl chains exhibited superior plasticizing efficiency compared to those with linear alkyl chains. The above results suggested that optimizing alkyl chain length and branching could further improve the plasticizing efficiency of 2,5-thiophenedicarboxylate plasticizers in PVC. Notably, 2,5-thiophenedicarboxylates showed greater polarity and improved migration resistance in non-polar solvents than commercial dioctyl phthalate (DOP), suggesting their potential application in PVC products exposed to non-polar environments.
研究领域:
高分子材料
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塑料加工
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增塑剂化学
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聚合物物理
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生物基材料
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DOI
高影响因子
Chemistry of Heterocyclic Compounds
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2021
·Vol. 57
·期 7
·806-816
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IF 1.277
An Xiaoying,Gao Lei,Wang Mingliang,Wu Haitao,Wang Lanzhi
Novel, efficient and environmentally friendly approaches have been developed for the synthesis of 1,5-benzodiazepine-2,3-dicarboxylates by one-pot three-component domino reactions in the presence of a catalytic amount of γ-Fe 2 O 3 @SiO 2 /Ce(OTf) 3 in EtOH at ambient temperature. A total of 32 2,5-dihydro-1 H -1,5-benzodiazepine-2,3-dicarboxylates and 2-methyl-2,3-dihydro-1 H -1,5-benzodiazepine-2,3-dicarboxylates with enamine or imine structure of the heterocycle, respectively, were obtained in good yields by reacting substituted 1,2-phenylenediamine, β-carbonyl esters, and ethyl glyoxylate or ethyl pyruvate. One-pot reactions were successfully realized to form one new cycle and four new bonds (one C–C, two C–N, one C=C or two C–C, one C–N, one C=N). Furthermore, plausible mechanisms for the formation of 1,5-benzodiazepine-2,3-dicarboxylates have been proposed. The salient features of this reaction include short reaction time, mild reaction conditions, moderate to excellent yields, recyclability of the catalyst, and wide substrate scope.
研究领域:
有机化学
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合成化学
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DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2025
·
IF 6.3
Xiaoqin Jiang,Meiling Chen,Jiyang Zuo,Tao Yang,Caiqi Liu,Kangpeng Liu,Siqi Yu,Fei Liu,Jinggang Wang,Jin Zhu
Bio-based materials provide solutions with both ecological benefits and technical feasibility for replacing traditional petroleum-based materials. This study focused on poly(propylene 2,5-furandicarboxylate) (PPF), a fully bio-based polyester with promising gas barrier properties. However, the lack of mechanical properties has become a key bottleneck in its packaging applications. Aiming at the problems of low molecular weight of PPF, Poly (propylene 2,5-thiophenedicarboxylate) (PPTh) oligomer prepared from 2,5-thiophenedicarboxylic acid and 1,3-propanediol was used to modify PPF, and high molecular weight poly(propylene 2,5-thiophenedicarboxylate-co-2,5-furandicarboxylate) (PPThF) copolyesters were prepared by melt polycondensation. The experimental results exhibited excellent CO 2 and O 2 barrier properties of up to 29.0 and 9.3 times compared with those of PET, respectively. Crucially, a brittle-ductile transition occurs without sacrificing barrier properties (elongation at break increases from 4.6% to 29%). These findings indicate that the material has the potential for packaging materials.
研究领域:
高分子材料
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包装材料
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生物基聚合物
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材料科学
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阻隔性能研究
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聚合物改性
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DOI
高影响因子
IRANIAN POLYMER JOURNAL
·
2025
·
IF 2.8
Wang Guoqiang,Wang Jianyu,Wang Yueying,Wei Deyu,Hui Yunfeng,Yu Yiheng,Zhang Mengke,Shi Longqing,Hu Hongliang,Jin Yujie
In this work, two high-molecular-weight polyesters poly(1,12-dodecylene terephthalate) (PDT) and poly(1,12-dodecylene thiophenedicarboxylate) (PDTD) were synthesized using geometrically distinct aromatic monomers: dimethyl terephthalate (DMT, 180° bond angle) or 2,5-thiophenedicarboxylic acid (TDCA, 148° bond angle), coupled with 1,12-dodecanediol (DD). Comprehensive characterization (chemical/thermal/crystalline/tensile/dynamicmechanical/rheological properties) revealed unique structure–property relationships governed by TDCA’s nonlinear geometry. The weight-average molecular weights of poly (1,12-dodecylene terephthalate) (PDT) and poly (1,12-dodecylene thiophenedicarboxylate) (PDTD) were 119,700 and 110,700 g/mol, respectively. Both polyesters were identified as semi-crystalline polymers by differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD). PDTD exhibited dual melting peaks (103.9 °C/94.3 °C), attributed to chain-folding constraints from TDCA’s angular distortion causing defective crystals, while PDT showed a single peak (124.1 °C). At the same time, the melting temperature of PDT is higher than that of PDTD, because the benzene ring is more conducive to the folding of the molecular chain. The decomposition temperatures at 5% weight loss of PDT and PDTD are 378 and 365 °C, respectively. PDT is more thermally stable than PDTD, because the benzene ring is more stable than the thiophene ring. PDT demonstrated polyethylene-like tensile strength (17.7 MPa) and melting temperature (124 °C). The results reported in this work provide deeper insights into the relationship between structures and properties of polyesters with long-chain diols, facilitating the design and synthesis of high-performance polyesters in the future. Graphical abstract
研究领域:
高分子化学
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材料科学
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高分子合成
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热分析
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聚合物表征
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DOI
高影响因子
LIQUID CRYSTALS
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2017
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IF 2.661
Cheng-Yan Gan,Jing Zhou,Wen-Hao Yu,Shi-Kai Xiang,Lai-Cai Li,Bi-Qin Wang,Ping Hu,Ke-Qing Zhao,Xiao-Zhen Chen,Chun Feng
Hexasubstituted triphenylene (1a) containing four alkoxy and two adjacent methoxycarbonyl tails can be smoothly brominated or nitrated at its α-position(s) of two electron-rich rings to give a series of bromides and nitro compounds through electrophilic aromatic substitutions. Positions of bromo or nitro groups in target compounds were unambiguously established by combined analysis of 2D nuclear magnetic resonance experiments including nuclear Overhauser effect and heteronuclear multiple-bond correlation which indicated that monobromination or mononitration occurred preferentially at position 8 or 5 of 1a, respectively. Calculations of molecular geometry on 2a–e reveal that the α-Br or α-NO2 group(s) would induce different degrees of helical deformation in the triphenylene core and the degree of non-planarity decrease in the following order: 2c > 2b > 2e > 2a > 2d. In contrast to highly twisted 2b–c and 2e, which did not form a mesophase, the formation of a hexagonal columnar phase at room temperature even down to −50°C was observed and confirmed by polarising optical microscopy and X-ray diffraction for sterically less hindered, monosubstituted 2a and 2d.
研究领域:
材料科学
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化学
·
液晶
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DOI
高影响因子
Catalysis Science & Technology
·
2018
·Vol. 8
·期 18
·4718-4725
·
IF 5.365
Jiang-Wei Shen,Jia-Mei Qi,Xiao-Jian Zhang,Zhi-Qiang Liu,Yu-Guo Zheng
Candida antarctica lipase B (CALB) is a versatile and robust lipase with high activity and enantioselectivity in the resolution of alcohols and amines. Poor specific activity toward carboxylic esters that are branched or substituted in close proximity to the carboxyl group limits the application of CALB. In this study, a semi-rational engineering approach was successfully applied to tailor CALB for efficient synthesis of the moxifloxacin chiral intermediate through enzymatic resolution of cis-(±)-dimethyl 1-acetylpiperidine-2,3-dicarboxylate. The combinatorial active-site saturation test was performed on CALB and two key residue sites, 189 and 190, were identified in the determination of hydrolytic activity. The specific activity and catalytic efficiency (kcat/Km) of the best variant mut-I189K were increased by 286- and 193-fold, respectively, without impacting its enantioselectivity. With 0.1 g L−1 of purified mut-I189K loading, 1 M substrate was asymmetrically hydrolyzed with 49.9% conversion within 5 h, resulting in a space–time yield of 583.8 g L−1 d−1. These results demonstrated that mut-I189K is a competitive biocatalyst for large-scale preparation of the moxifloxacin chiral intermediate.
研究领域:
生物催化
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酶工程
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药物化学
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有机合成
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2023
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IF 3.8
Hai-Xia Xu,Hui Chen,Zhong-Ping Yin,Qing-Feng Zhang
s Inhibition of α-glucosidase and non-enzymatic glycation is an effective approach to treat type 2 diabetes. Piceid (PI) is a potential α-glucosidase inhibitor and antiglycation agent found in many plant-based foods and herbs. To enhance the liposolubility and hypoglycemic effects of PI, two PI dicarboxylic acid esters were synthesized via enzymatic acylation in green solvents using dicarboxylic acids with hypoglycemic activity as acyl donors. Their structures were characterized by HPLC, HRMS, and 13 C NMR. Also, the antiglycation and α-glucosidase inhibitory effects of PI derivatives were investigated by enzymatic kinetics, CD, bovine serum albumin (BSA)-fructose model, FTIR, and molecular docking analysis. The results found that the introduction of dicarboxylic acid molecules significantly enhanced liposolubility, antiglycation, and α-glucosidase inhibitory activities of PI. The IC 50 values of two PI derivatives on α-glucosidase were nearly 9.9-fold and 16.2-fold lower than native PI, respectively. Moreover, the dicarboxylic acid moieties in PI derivatives induced the conformational changes of α-glucosidase, which made the secondary structure of α-glucosidase tighter, thus hindering the entry of substrates. Molecular docking results showed that PI derivatives could insert into the active pocket of α-glucosidase and interact with more key amino acid residues than PI. Also, PI derivatives could block the glycation sites of BSA.
研究领域:
药理学
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化学
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生物化学
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分子生物学
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糖尿病研究
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高影响因子
危险品化学品经营许可证（带存储）